Fire-alarm.



C. G. UARLSON.

FIRE ALARM.

APPLICATION FILED AUG.2G,1911.

1,023, 1 23, Patented Apr.16,1912.

@62M l 10 o UNITED 'STATES PATENT OFFICE. l

CARL GERHARD CARLSON, OF CHICAGO, ILLINOIS.

FIRE-ALARM.

To all whom it may concern:

Be it known that I, (laan GERHARD CARL- sox, a citizen of the United States, residing at the city of Chicago, county of Cook, and State of Illinois, have invented certain new and useful Improvenients in Itire-r-Xlarms, of which the following is a specification.

My invention relates to improvements in alarm devices and more specifically to a de-` vice of this character especially adapted for use in the spreading of alarm in vcase of tire.

The object of my invention is the production of a fire alarm which will be automatic in its operation and one which will be of Adurable. and economical construction and which will be positive and etiicient in operation.

Other objects will appear hereinafter. Tith these objects in view my invention consists in a fire alarm characterized as above mentioned and in certain details of construction and arrangements of parts, all

` closing device included in my invention,

and Figs. 3 and 4 are sections taken on substantially lines azand g/-g/ respectively of Fig. 2.

The preferred form of my construction as illustrated in the drawing comprises an electric circuit in Which is included a battery l or any other suitable source of electric energy. Connected in shunt with the main circuit is a plurality of electric bells or other suitable electricalarm devices 2. Also arranged 1n the mam circuit at the opposite side of the batteryl is a plurality of I circuit closing devices 3 which are also connected in shunt With said main circuit. The arrangement is such that normally the main circuit is open, closing thereof in order to effect actuation of the alarm devices 2 being effected through the medium of said circuit closing devices, closing of any one of said circuitclosing devices effecting the closing of the circuit and hence the sound ing of the alarm devices.

Specification of Letters Patent.

Application filed August 26, 1911.

APatented Apr. 16, 1912.

serial No. 646,089.

Each of the circuit closing devices 3 com` prises a circular base 4t formed of any suitable insulating material. Mounted upon the front side of the base 4 is a stationary contact 5 and a spring contact (5, said contacts being secured `in position by screws or other suitable securing devices 7, binding posts S being connected with the rearward ends of the screw 7 of contact. 5 and one of the screws 7 of the contact G for :tacilitating the connection of the wires or electrical conductors with said contacts. The spring contact 6 is so arranged and designed that normally the free end thereof will engage the contact 5, said end. of said spring contact being held out. of engagement with the stationary Contact b v a cord t) which passes around said free end. the outer end of said cord engaging over the central portion of a substantially U-shaped frame IOthecXtremities of which are rigidly secured in the base member Ll. The frame l() and the free extremity of the contact G are so formed as will be observed as to be adapted to maintain the cord 9 in proper position, this object being accomplished by a. kink 10 which...rv

is provided in said frame anda similar construction of the free end of said contact.y as

clearly shown in Fig. 3. The cord- 9' ,iS formed of any suitable inflammable material so that in the event of lire inthe vicinity of its location causing burning` thereof it will effect the release of the contact 6 and the establishment of electrical connection between the contacts 5 and 6, the latter because of its inherent resiliency moving into engagement withtlie contact 5 upon being released.

The contacts 5 and 6 are inclosed in a suitable casing or housing ll which is se cured upon the base member t by screws 12. The front side of the casing l1 is provided with perfor-ations 13 to permit of the passage of the cord 9. The casing ll is provided to prevent the accumulation of dust or dirt upon the contacts 5 and 6 and so as to maintain thesurface thereof clean so that when the end ofthe contact G is brought into engagement with the outer surface of the contact 5 an efficient electrical connection will be established.

In using my device the alarm devices 2 are distributed throughout the building at suitable locations, preferably in sleeping apartments, where the device is installed in an apartment building or hotel. The circuit great headway has been gained.

closing devices are similarly distributed preferably in such locations as it is thought thatvres are most likely to start, it .being clear that although only three .of each ,of the devices are shown, any number may be employed and connected with the main circuitin the same manner as shown. When so connected it will be seen that in the event of a fire in the building where the fire alarm system is employed, upon the flame destroying any one of the cords 9 of the several circuit closing devices, the main circuit will be immediately closed and the alarm given so that the occupants of the building may escape and the tire be extinguished before any A ire alarm device or system of the construction set-forth is simple and economical and hence may be installed at a very low cost, and the same is of high eciency in use.

While I have illustrated anddescribed the preferr d construction for carrying my invention in o cft'ect, the same is capable of variation or modification without departing from the spirit of the invention. I therefore' vdo not wish to be limited to the exact vdetailsvof construction as set forth but desire to avail myself of such variations and modifications as come within the scope of the appended claim.

Having illustrated and described my invention, what I claim as new and desire to secure by Letters Patent is:

A fire alarm comprising a normally open electric circuit; an alarm device in said circuit; an insulating base member; a contact member on said base member and in said circuit; a spring contact on said base and in said circuit and arranged to contact with said first mentioned contact to close said circuit; a hemispherical 'casing secured to said base and inclosing said cont-acts, there being two openings in the top of said casing; a frame secured to said base member and passing over said casing; and an inflammable cord tied in a loop passing over said frame. under said spring contact and through said openings, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of 1two subscribing Witnesses.

CARL GERHARD CARLSON. lVtnesses z HELEN F. LILLIS, ARTHUR A. OLSON. 

